Although ventilation and airtightness are covered in most countries by various regulations focused on energy performance and/or indoor air quality, the effectiveness of these regulations is often called into question. A number of studies have shown significant deviations between assumed and actual characteristics of the building or equipment, possibly resulting in non-compliance to the regulation and/or degraded performance. The principal objective of this workshop was to discuss and identify ways to reduce these deviations with or without regulatory measures, thereby increasing the confidence in declared values of documents produced to show compliance with the regulations. Three aspects were more specifically addressed: how to improve the reliability of the input data used to issue Energy Performance certificates; how to improve the quality of the works; how to take into account innovations in a compliance framework. The workshop discussions were based on detailed presentations of schemes that are operational or under development to address those issues.